CD8⁺ T cells are critical mediators of cytotoxic effector function in infection, cancer and autoimmunity. In cancer and chronic viral infection, CD8⁺ T cells undergo a progressive loss of cytokine production and cytotoxicity, a state termed T cell exhaustion. In autoimmunity, autoreactive CD8⁺ T cells retain the capacity to effectively mediate the destruction of host tissues. Although the clinical outcome differs in each context, CD8⁺ T cells are chronically exposed to antigen in all three. These chronically stimulated CD8⁺ T cells share some common phenotypic features, as well as transcriptional and epigenetic programming, across disease contexts. A better understanding of these CD8⁺ T cell states may reveal novel strategies to augment clearance of chronic viral infection and cancer and to mitigate self-reactivity leading to tissue damage in autoimmunity.

CD8 ⁺ T 细胞是感染、癌症和自身免疫中细胞毒性效应子功能的关键介质。在癌症和慢性病毒感染中，CD8 ⁺ T 细胞会逐渐丧失细胞因子的产生和细胞毒性，这种状态称为 T 细胞衰竭。在自身免疫中，自身反应性 CD8 ⁺ T 细胞保留有效介导宿主组织破坏的能力。尽管每种情况下的临床结果不同，但 CD8 ⁺ T 细胞在所有三种情况下都长期暴露于抗原。这些长期受刺激的 CD8 ⁺ T 细胞在各种疾病背景下具有一些共同的表型特征，以及转录和表观遗传编程。更好地了解这些CD8 ⁺T 细胞状态可能会揭示新的策略，以增强慢性病毒感染和癌症的清除，并减轻导致自身免疫组织损伤的自我反应。